Computing devices, e.g., smart phones, MP3 players, laptops, workstations, that are connected to each other form a network. Networks are often configured as private networks, such that members of a private network have private IP addresses. In this manner, computing devices outside of the private network cannot communicate directly to the members of the private network. Such private networks are also referred to as local area networks (LAN). At least one of the members of the private network, e.g., a server computing system, is often configured with both private and public IP addresses. In this manner, devices outside of the private network can communicate directly to the server computer system of the private network that also has a public IP address. In this example, although the server computing system that has both private and public IP addresses is a member of the private network, it is also a member of a public network, e.g., the Internet.
As such, a server computer system is often configured to provide a first set of services to “internal” clients (e.g., to computing devices that communicate with the server computer system using corresponding private IP addresses), and a second, typically smaller set of services to “external” clients (e.g., to computing devices that communicate with the server computer system using corresponding public IP addresses.)